Introducing the Japanese approach to Waste Water System; Recycle of Sewage Sludge & Sewer Rehabilitation

Transcription

1 International Water Summit Abu Dhabi, 21 st Jan 2014 Introducing the Japanese approach to Waste Water System; Recycle of Sewage Sludge & Sewer Rehabilitation Yosuke Matsumiya

2 Basics JP Population:130 million Service Accessibility Ratio: 76% Number of WWTPs: 2,145 Sewer Length: 443,000 km Annual Sludge Gen: 2.3 million DS ton

3 Recycle of Sewage Sludge Sewer Rehabilitation

4 Most sludge is recycled as construction material. Small farming limits agricultural recyle. Incineration is common for stabiliaztion due to high pop density. Cement companies charge utilities. 20% Landfill 80% Recycled Dry Solids Basis From website of MLIT, Gov of Japan 20% Agri. 30% Other Const. 50% Cement

5 Example-1: Sludge Melting slag for construction gravel & sand, easily recyclable. containing HM pollution. Slag is sellable. Problem is energy intensive

6 Air Coolant Ash Exhaust Coolant Slag nkai.html

7 From Kobelco Website in Japanese For more info,

8 Example-2: Filling Soil Incineration ash plus waste soil to be filling soil for installation. Recycle completes within operator domain. No need to worry about market.

9 Example-3: Concrete Products Manufactured using ash from incinearaion ash. Utility buys with priority to advance recycles.

10 But organics is not recycled much. Quick stabiliation by incineration has been main. Digestion/biogas use has been sidelined. 10% Agri. 10% Biogas 80% Unused

11 Need to Increse Energy Use Reduction of the GHGs by Green Energy Use Loss of Nuclear Power Explosion of Nuclear Plant after Tsunami

12 Unique Biomass Energy Use, not conventional Biogas Use Biogas Biogas Powered Fuel Cell Micro Gas Engine Food Waste Disposer Biochar 12

13 Exp-1: A WWTP, 100,000m3/d, KUMAMOTO. Fuel cells, 4 units of 100kw, supply half power. No emission. Promising tec. OPEX is coming down. For more info,

14 Exp-2: A WWTP, 98,000 m3/d, in SAGA. Resonably priced micro gas engines, 16 units of 25kw. Generate half of power. For more info,

15 Exp-3: A WWTP, 22,000m3/d in KUROBE. As biomass recycle center in the city. Disposer installation encouraged at houses, to increase biogas & to reduce solid waste generation. Accepting food factory waste. Biogas supply half power. Dried sludge is transported & used at Coal Fire Power Plant. 15

16 WWTP Power Biogas Generator Power Plant Thickened Sludge Digester Dehydrator PFI Drier Dried Sludge Food Waste

17 Biochar Production Projects have been increasing Carbon neutral fuel at coal fire power plant Carbon negative for soil fertility improvement 17

18 Capacity of Biochar Production on Dewatered Sludge basis Tokyo: 300t/d since 2007 Hiroshima: 100t/d since 2012 Aichi: 100t/d since 2012 Kumamoto: 50t/d since 2013 Several others already in pipeline

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20 Recycle of Sewage Sludge Sewer Rehabilitation

21 Annual Installation (*1000km) Total Installation Rapid sewer aging feared due to short term intensive installation Total 440,000km 10,000km Over 50 yrs

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23 Trenchless rehab has started. Lining with cured-in-place pipes (CIPP) Lining with spirally-wound pipes Lining with close-fit pipes Pros and cons exist for the methods. 23

24 Spirally-wound pipes Reliable but costly Can install with live flow Any shape of section

25 CIPP Less costly Difficult in QC Need to Stop Sewage

26 Close-fit Moderately reliable & costly Need to stop sewage winch Boiler liner

27 Overall Trend & Discussion in JP Big Diamater Spirally Wound Pipes Small Diameter CIPP followed by Close-Fit QC & Long-Term Performance is discussed

28 Discussion of Surface Irregularity ISO , 6mm or 2% of Dia., greater 1.2m D=300mm Water Manometer Liner Model Experiment Result In case of 6mm in roughness depth at 10cm intervals, flow capacity reduces to 80%. 23m

29 Thanks!